There are many applications for polymers prepared from components by polymerization reactions that can be conducted at relatively low temperatures, for example, at or below ambient temperatures, and that proceed without the evolution of volatile byproducts. Such polymers can be used, for example, for the manufacture of large plastic parts without the necessity of providing special techniques and apparatus for removing volatiles from the reaction in order to avoid undesirable product porosity.
In addition the elimination of any need to employ curing agents, catalysts, and the like to procure satisfactory curing of the desired polymers is of significant advantage.
While some processes that display such characteristics, for instance, nucleophilic additions to epoxides and isocyanates are widely used, the reactions thus obtained have the disadvantage of being susceptible to a number of competing side reactions that diminish their attractiveness. In this regard, isocyanate compounds are susceptible to dimerization reactions, while epoxides experience a variety of reactions that make them useful chiefly in applications that require thermosetting resins.
Furthermore, it is frequently of considerable advantage if the reacting components of a polymerization system are of a liquid or low-melting type, such characteristic assuring that their mixing and application can be accomplished with minimal difficulty. This is of particular importance where the components of the polymerization system are to be employed, for example, in high-speed, reaction injection molding (RIM) processes. Liquid polymerization components are also of considerable benefit in adhesive applications, in fabricating composite products, and in many other areas.